Apparatus for holding plates or sheets upon surfacing tables



.J. H. FOX

APPARATUS FOR HOLDING PLATES OR SHEETS UPON SURFACING TABLES Filed June 10, 1925 3 Sheets-Sheet 1 Lwwm J. H. FOX

APPARATUS FOR HOLDING PLATES 0R SHEETS UPON SURFACING TABLES 1925 3 Sheets-Sheet 2 INVENTOR f/C Filed June 10 Sept, 7 we. 1,598,766

J. H. FOX

APPARATUS FOR HOLDING PLATES OR SHEETS UPON SURFACING TABLES Filed June 10 I 1925 3 Sheets-Sheet 3 INVENTOR Patented Sept. 7, 1926.

UNITED STATES 1,598,766 PATENT OFFICE.

JOHN H. FOX, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR T0 PITTSBURGH PLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

APPARATUS FOR HOLDING PLATES OR SHEETS UPON SURFACING TABLES.

Application filed June 10, 1925. Serial No. 36,130.

and attention required for looking after the system is reduced to a minimum, by the use of'means which render the operation of securing the vacuum and maintaining it largely automatic; and the provision of improved means for insuring constant and effective application of the suction to the glass sheets throughout the surfacing operation. Certain embodiments of the invention are illustrated in the accompanying drawings wherein:

Figure 1 is a longitudinal section through the apparatus on the line II of Fig. 2.

Fig. 2 is a transverse section on the line 'IIII of Fig. 1. Fig. 3 is a diagrammatic plan view ofone of the cars or tables. Fig. 4 is an enlarged longitudinal section, also taken on the line II of Fig. 2. Fig. 5 is a detail sectional view of the line V-V of Fig. 3. And Fig. 6 is a transverse section through a modified form of table.

Referring to the drawings, 1, 2, 3, etc. are three of a series of tables constituting a train mounted upon the track 4 and ada ted to be moved beneath a series of grin ing and polishing machines. The runner 5 of one of the grinding machines is shown, such runners being of any desired type and being driven in any desired manner. Similar- 1y as to the runners of the polishing machines beneath which the series of cars are carried after the grinding operation is completed.

The surfacing tables are all similar in construction and comprise a cast body portion 6 supported upon three pairs of wheels 7 7, 7. The upper surface of the table is preferably provided with the sets of grooves 8, 9, etc., as indicated in Fig. 3, in which two only of the sets of grooves are shown. The grooves may be cut into the metal of the table as indicated in Fig. 4, or the upper surface of thetable may be provided to setting the sheet and the va with a covering of rubber 10, as indicated in Fig. 5,in which case, the grooves are cut in the rubber. Each of these grooves has leading downwardly therefrom an exhaust tube, such as the tube 11, shown in Fig. 4, and the tube 12 shownin Fig, 5, and these tubes are all connected with a vacuum chamber or manifold 13, extending longitudinally of one side of the table, as indicated in Figs. 1 and 3. These tubes are rovided with check valves 14 and 15 yieldingly pressed upward by means ofthe springs 16v and 17. The tubes 11 all lie directly above the manifold 13, so that no lateral connection is required, but in the case of the tubes 12, the lateral connections 18 are required which extend transversely across the table and into the manifold 13, as indicated in Figs. 2 and 3. It is desirable, in order to improve the contact between the sheet of glass and the table, to provide a layer of water upon the top of the table reliminary 15 serve to prevent this water from running out preliminary to the application of suction to the pipes 11 and 12.

The manifold 13 of each table is preferably provided with a pair of outlets which are yieldingly held closed by the valves 19, 19 (Figs. 1 and 4). The valve stems are suitably guided in spiders 20 carried by the valve seats 21 and are pressed upward by means of the springs 22. Extendmg longitudinally beneath the track 4 is the vacuum line 23. in the form of a large diameter in order to provide the system with a large exhausting capacity per unitof time. This line is exhausted from the pump 24 driven from the motor 25 and having a suction pipe 26 leading to the line 23.

The vacuum line 23 is preferably located beneath the floor 27, and at suitable intervals, vacuum intakes or terminals are located, such terminals or intakes bein adapted to apply suction to the manifol s 13 as the cars pass over such terminals. These terminals-are in the form of elongated intake members or heads 28 carried by the hollow stems 29 mounted for vertical movement in the brackets 30 carried by the floor. The stems 29 are yieldingly pressed upward by means of the counterweighted levers 31 fulcrumed at 32 and having their hook shaped ends 33engage trunnions 34 upon the elbows pipe of relatively ves 14 and 35. These elbows 35 are connected by flexible tubing or hose 36 to the fittings 37 communicating past the valves 38 with the vacuum line 23. The intake member or terminal 28 has a lip 39 adapted to contact with the lower surface of the manifold 13, and in order to make a tightcontact, the lip 1s provided with a suitable packing 40.-

In order that the terminal orhead may come in contact with the manifold 13 without jar or shock as the table moves along the track, the ends of the manifold are inclined, as indicated at 41 (Fig. l). The passage through the stem 39 is normally held closed by means of a valve 42, the action of gravity being supplemented by the spring 43, so that when the terminal or head 28 is not in contact with the manifold 13, there is no leakage of air through the stem. Means are provided for automatically opening the valve 42 in the form of the lever 44 pivoted at 45 and normally swung upward by means of the spring 46. This lever carries at its outer end a roller 47 adapted to engage the cam 48 located on the bottom of the manifold 13. The pin 45 which carries the lever also carries a tappet 49 adapted to engage the stem of the valve 42 and move it upward when the roller 47 is en gaged by the cam 48. In operating the apparatus, the surface of one of the tables is covered with a film of water and the sheet of glass is applied thereto, after which the table is moved alon the track until it arrives at the position lndicated in Figs. 1 and 4, at which time the intake member or head 28 registers with or lies over the opening into the manifold controlled by the valve 19. At this moment, the cam 48 engages the roller 47, causing the opening of the valve 42 so that suction is applied from the vacuum line 23 to the space between the head 28 and the manifold 13, thus opening the valve 19 and exhausting the air from the manifold and from the tubes 11 and 12 and giving a suction effect in the grooves 8 and 9. The glass sheet is in this manner held securely against the top of the table by the artial vacuum induced by the operationas ust described. As the table moves along still farther over the intake or terminal .28, such intake is brought out of registry with the valve 19 and the cam 48 is brought out of engagement with the roller 47 and the valves 19 and 42 close. This condition is maintained until the head or terminal 28 comes over or registers with the next valve 19 on the manifold, when the operation as just described is repeated. In this. manner, there are two exhausting operations upon each manifold, thus giving a better exhaustion of the air, although this could be sufliciently accomplished by having onlya single exhausting operation upon each manifold.

The glass 1s now securely applied to-the table, but during the continued grinding and polishing operation, a part of this vacuum may be lost, due to leakage, or-

due to the cracking of the glass, so

that it is desirable to renew the vaclength of travel of the tables. In case the glass is cracked, the leakage is very rapid, and it is under this condition that a large capacity in the vacuum line 23 becomes desirable, so that at each exhausting terminal, a very substantial degree of exhaust or suction may be applied. The pipe 23 is therefore made as large in diameter as can be reasonably done and the motor and pump are operated to maintain as high a degree of vacuum in thisline as is possible.

Fig. 6 illustrates a modification in which the manifold 13 of Figs. 1 to 5 is dispensed with, and in place of such manifold, a chamber 50 is provided in the body of the car 51. This chamber is provided with connections 52 and 53 corresponding to the connections 11 and 12 of the Fig. 1 construction, and the lower wall of this chamber is also provided with valves similar to the valves 19, 19 of the other construction. The

rest of the construction, including the exhaust heads or terminals is the same as in the Fig. 1 construction.

What I claim is 1. The combination with a surfacing car or table mounted Ifor movement along a track and having a glass supporting surface, an exhaustin chamber havin communication with such surface provide with an outlet having a check valve, a vacuum terminal or intake member mounted adj acent' the path of movement of the table and adapted to register with said outlet as the table moves past it, means for applying suction to said member, a valve for said member, and means for opening said valve when said member is brought into registration with said outlet.

2. The combination with a surfacingcar or table mounted .for movement a'lon a track and havin a glass supporting sur ace,

an exhausting c amber havin communication with such surface provided with an outlet having a check valve, a container of relativelylarge capacity from which the air- 15 exhausted located adjacent the track, a,

vacuum intake member or terminal connected to said container'and mounted in position to register with said outlet as the table .moves past it, a valve between the terminal ngesnee an exhausting chamber havin communica tion with such surface provide with an outlet having a check valve, a plurality of vacuum intake vmembers or terminals arranged in series along the path of movement of the table. and adapted to register successively with said outlet, a conduit from which the air is exhausted connected to said terminals,

a valve between each of said terminals and the conduit, each held yieldingly in closed position, and means operated by the movement of the table for opening each of said valves as said outlet arrives in registration with the terminal for which the valve acts as a closure.

4. The combination with a surfacing car or table mounted for movement along a track and having a glass supporting surface, an exhausting chamber having communication with such surface provided with an out let having a check valve, a plurality of vacuum intake members or terminals arranged in series along the path of movement of the table and adapted to register succes sively with said outlet, a conduit from which the air is exhausted connected to said terminals, a valve between each of said terminals and the conduit, each held yieldingly in closed position, means for pressing the terminals forward so that'they yieldingly engage the table surrounding said outlet during the movement of the table past the terminals, and means operated by the movement of the table for opening each of said valves as said outlet arrives 1n registration with the terminal for which the valve acts as a closure. g

5. The combination with a surfacing car or table mounted for movement along a track and having a glass supporting surface, an exhausting chamber having a bottom wall with a downwardly facing horizontal surface and an opening therethrough provided with an upwardly opening check valve, an exhaust intake or terminal beneath the table opening upwardly and adaplted to engage said horizontal surfaceas t e table moves past the terminal, a suction line communicatmg with the terminal, a valve normally closing ofl' communication between the terminal and the suction line, and means actuated by the movement of the table over the terminals for opening said valve.

\ 6. The combination with a surfacing car or table mounted for movement alon a track and having a glass supporting sur ace, an exhausting chamber having a bottom wall with a downwardly facing horizontal surface and an opening therethrough pro vided with an upwardly opening check valve, an exhaust intake or terminal beneath the table opening upwardly and yieldingly pressed upward, and adapted to engage said orizontal surface as the table moves over the terminal, -a suction line communicating with the terminal, a valve normally closin ofi communication between the terminal an the suction line, and means actuated by the movement of the tableover the terminal for opening said valve.

7. The combination with a surfacing car or table mounted for movement along a track and having a glass supporting surface, an exhausting chamber having a bottom wall with a downwardly facing horizontal surface and an opening therethrough provided with an upwardly opening check valve, an exhaust intake or terminal beneath the table opening upwardly and yieldingly pressed u ward, and adapted to engage said horizonta surface as the table moves over the termlnal, a suction line communicating with the terminal, a valve normally closing off communication between the terminal and the suction line, and cam means on the table for opening said valve as the table moves over the terminal and while the ter minal openin is in registry with said opening through t e bottom wall of said exhausting chamber.

In testimony whereof, I have hereunto subscribed my'name this 6th day of June,

JOHN. H. FOX. 

